Method of making bolt-nuts



C. I. MAIIYE.

METHOD 0F MAKING BOLT NUTS.

APPLICATION FILED FEB. I, I9I9.

PatentedSept. 13, 1921.

WI-TNESSES:

PATENT OFFICE. i

enmarcan I. mAaYE, oF CHICAGO, ILLINOIS, AssIGNoa To MABYE sari-:TY NUT CORPORATION, A CORPORATION ILLINOIS. t

METHOD OF MAKING BOLT-NUTS.

Specification of Letters Patent.

Patented Sept. 13, 1921.

Application led February 1, 1919. Serial No. 274,447.

To all whom it may concern:

Be it known that I, CLIFFORD P. MARYE, a citizen of the UnitedStates,` residing at (Jhicago, in the county of Cook and State of Illinois, have invented certain new and useful Improvementsin Methodsf of Making Bolt-Nuts, of whichthe followingis a specification.` p p i M invention relates to a method of making holt nuts and has especial reference to self securin nuts.

One of t e objects `of the invention is to provide a method of procedure for simultaneously milling all ofthe c onvolutions of i t erate aun-uniform lead to the threads.`

t threa Another object of my invention is to provide a method of making bolt nuts, in one- `form of which the `threads-are -anomalous, but in which the thread `pitch of the convolutions areunform, with respect to each In ursuing my mode of "procedure the which may be doneby the use of a milling tool, ,beiner made tobear upon one side of the axis of the nut insuch manner that the initial points of all of the convolutions are thereby defined and out at one and the same time and while the cutting operation is being performed, by the rotating milling tool, the tool and nut are relatively moved about the axis of the tool and at the same time they v are relatively moved in an axial direction to define the pitch and character of the threads. In some instances this axial movement may be effected ata varying or un-uniform speed rate with respect to the other said movements. The result of this latter procedure is that the threads of the nut are made to diverge from a truespiral, thereby producing inthe threads a deviation from the true pitch line, by departing from the pitch line to a greater or less extent in either or both directions, but maintaining a uniform pitch of the threads with respect to each other.

A nut having aberrant or waved threads of this character, when turned upon a bolt t threads within the nut.

`waved threads of the .nut

s are made `in the bore of the nut,

having threads of uniform spiral configuration, of the standard type, will cause an abnormall friction engagement between the threads `of the :nut and of the bolt, which exerts a stress tending to straighten` the threads of the nut into a true `spiral formation, corresponding with the threads of the bolt, and some resilient displacement of the threads o. the nut will take place in' order to accommodate themselves to the thread of the bolt, and the `threads of the bolt are similarly stressed to conform to the character of The efect'of the-axially undulating or and of the normal slplral threads of the bolt, is such that the t reads of one will be caused to conform to a greater or less extent, to the threads of the ot erV without destruction of thethreads of either the -nut or the bolt, and therefore, when the strain is released, by `unscrewing the nut from the bolt the threads of each will reassume `to a greater or less extent, their normal relative positions. Therefore, the` nut may be threaded or turned upon the bolt and retracted and removed therefrom a number of times, without ,causing material variation in the resistance to movement, as a result of the peculiar character of the encountering threads.

In the accompanying drawings forming part hereof: Y

Figure l is an enlarged diametrical section of a nut made in accordance with my methodof procedure.` f

`F ig. 2 is a milling tool, that may be employed in making the nu 4 Fig. 3 is a schematic representation of a means for carrying my invention into effect.

In all the views the same reference characters are employed to indicate similar parts.

I have shown a nut having anomalous threads, made by my method of procedure, because the standard nut having threads of true spiral formation and that may be made by practice of my invention is familiar and well known;

The nut 5 is provided with a series of threads having two bolt-entrant convolutions 6 and 7, somewhat` larger in diameter than the convolutions 8, but of the same pitch and character as the convolutions of the remaining portion of the threaded spiral. The object of this is to permit the bolt to enter freely into the nut and into threaded vWhile the remaining teeth Will cut the threads in the lmain body of the nut.

In carrying my invention into effect I rotate the cutter 9 at a relatively high velocity to give it cutting effect and so present the nut tothe cutter that the cutter Will cut all of the thread convolutions in one side of the nut orifice at one and the same time. After the cutter has been set into rotation, at suitable velocity, the nut` and cutter are relatively moved with respect to each other in a direction at substantial right angles to their respective axes, so :that the vteeth of the cutter Will cut-into the 'standard nut a distance 'requisitefor the depth of the threads.

f After this has been donethe nut and cutter l are then relatively moved about their axes,

andcoincidently are axially moved with respect toeach other to determine the lead or pitch lineand character'ofY the threads. In order to produce the threads of the peculiar Wave character "disclosed herein, the axial movement of the nut or cutter, lor both, is not uniform, but to the contrary, the rate of movement yis variable. 1f this movement were *uniform v then a nut having threads forming'fa true spiral, would be produced, V-but inasmuchas this movement is not uniform, the spiral isnot a true one, but resembles the structure clearly depicted in the drawings.

'Therinilling cutter 9, must be rotated and forfthis purpose I have shown a spurY gear 22 in .mesh with the pinion 28 vivhicli directly 'rotates the cutter. They handle f 211 is a means Which rotationmay be effected,

The diametric movement' of the nut, with respect to the cutter may be effected by the screw 25, rotatable by the handle 26. The cam 27, in association with the fixed part 28, will advance the nut axially toward the cut ter at a speed rate determined by the configuration of the cani groove 27. The cani and nut may be rotated by means of the handle 29. One revolution of the cam 27 Will be sufficient to define all of the threads Within the nut and the axial movement of the nut is progressing While its rotative movement is being effected.

Of course, the cutters may be axially moved toward the nut or they may be moved axially toward each other While the threads are being circumferentially extend ed Within this nut orifice. If this movement is uniform, threads of a standard nut will be produced and if it is irregular the threads will be correspondingly irregular, similar in configuration to the nut illustrated herein.

Having described my invention, what I claim is Y 1. Steps in the method of making bolt nuts which consists in producing the threads of all of the convolutions coincidentally; by continuing the thread producing operation circumferentially throughout the interior of the nut opening and axially advancing the thread formation at an irregular speed rate during said operation to produce an anomalous thread spiral. y

2. Steps in the method of forming screw threads which consist in producing the threads of all of the convolutions of a threaded object coincidently by continuing the thread producing operation circumferentially throughout the threaded region and axially advancing the thread formation at an inconstant speed rate during said operation to produce an anomalous thread spiral.

In testimony whereof I hereunto suhscribe my name.

CLIFFORD P. MARYIQ.v 

